Left atrial remodeling in acute anterior myocardial infarction

BACKGROUND: Our goal in this study was to examine the changes in the left atrial functions over a period of 3 months by using left atrial volume measurements in patients with anterior myocardial infarction (MI). METHODS AND RESULTS: Seventy-three patients with anterior MI who consulted our hospital in the first 12 hours starting from the onset of the chest pain and who exhibited ST elevation were enrolled in the study. The left atrial functions of the patients were evaluated by transthoracic echocardiography for a total number of four times; first at the time of the visit to the hospital, then in the first week, and then in the first and third months. Eight (10.95%) of the 73 patients included in the study died during the follow-up. The remaining 65 patients completed the 3-month study period. Of these 65 patients, primary percutaneous transluminal coronary angioplasty (PTCA) was performed for 24 (36.9%) patients and thrombolytic therapy was given to 13 (20%), whereas 28 (43.1%) patients were given only medical treatment. Left atrium (LA) maximum transverse diameter, LA maximum, minimum, and presystolic volume, LA active emptying volume and fraction were found to increase significantly in comparison to baseline detected for this parameter in the first and third months (P < 0.001). However, LA passive emptying volume and fraction was found to decrease significantly in comparison to baseline detected for this parameter in the first and third months (P < 0.001). CONCLUSIONS: An increase in the diameter, volume, and dimensions of LA during atrial remodeling was detected. LA passive emptying fraction was found to decrease, whereas atrial active emptying function was found to increase to compensate for this change.     

Left ventricular thrombosis after anterior myocardial infarction with and without thrombolytic treatment

Abstract. Objectives. To examine the incidence of left ventricular thrombus in patients with anterior myocardial infarction, with and without streptokinase treatment. To identify predictors of thrombus development. Design. Consecutive patients prospectively studied during the hospitalized period. Echocardiography was performed within 3 days of admission and before discharge. Setting. Umeå University Hospital, a teaching hospital in Northern Sweden. Subjects. Ninety-nine patients with anterior myocardial infarction of whom 74 were treated with streptokinase. Main outcome measures. Left ventricular thrombus and left ventricular segmental myocardial function. Results. During the hospital stay, a thrombus developed in 46% (95% confidence interval [CI], 35–57%) of the patients in the thrombolysis group and in 40% (95% CI, 21–59%) of the patients in the non-thrombolysis group. No difference in left ventricular segmental myocardial function was found between the thrombolysis and non-thrombolysis groups at hospital discharge. No embolic events were observed. The occurrence of a left ventricular thrombus at hospital discharge was significantly associated with previous myocardial infarction, peak enzyme levels, left ventricular global and segmental dysfunction and an increased dose of peroral diuretics or use of parenteral diuretics. In a multiple logistic regression model, left ventricular segmental dysfunction was the most important predictor of left ventricular thrombus. Conclusion. Thrombolytic treatment with streptokinase does not prevent the development of a left ventricular thrombus but the risk of embolic complications is low. The left ventricular segmental myocardial score can be used to assess the risk of thrombus development, also, after thrombolysis.     

Early mitral regurgitation after acute myocardial infarction does not contribute to subsequent left ventricular remodeling

BACKGROUND: It is well known that mitral regurgitation may lead to left ventricular dilation; however, the relationship between progressive left ventricular dilation after acute myocardial infarction (MI) and mitral regurgitation has not yet been clarified. HYPOTHESIS: This study tested the hypothesis that early mitral regurgitation contributes to left ventricular remodeling after acute MI. METHODS: We prospectively evaluated 131 consecutive patients by serial two-dimensional and Doppler echocardiography on Days 1, 2, 3, and 7, after 3 and 6 weeks, 3 and 6 months, and 1 year following acute MI. Patients were divided into two groups: those with mitral regurgitation in the first week after acute MI (Group 1, n = 34) and those without mitral regurgitation (Group 2, n = 81). RESULTS: Over 1 year, a significant increase in end-diastolic volume index (from 62.1 +/- 12.9 to 70.5 +/- 23.6 ml/m2, p = 0.001) with a strong linear trend (F = 15.1, p < 0.001) was noted. Initial end-diastolic volume index was higher in Group 1 (65.6 +/- 13.3 vs. 60.4 +/- 12.5 ml/m2, p = 0.047), but this difference remained constant throughout the study (F = 1.76, p = NS). Therefore, the pattern of end-diastolic volume changes was similar in both groups during the period of observation. CONCLUSIONS: These data indicate that early mitral regurgitation after acute MI does not contribute to subsequent left ventricular remodeling in the first year after myocardial infarction.     

Predictors of early and late ventricular remodeling after acute myocardial infarction.

BACKGROUND: The determinants of the early and late stages of the ventricular remodeling process after infarction are not well defined. HYPOTHESIS: The study was undertaken to evaluate the factors that condition the time course of left ventricular dilation during the first 6 months after infarction. METHODS: The study group consisted of 74 patients with a first intermediate-large (> or = 4 Q waves) acute myocardial infarction. Contrast left ventricular and coronary angiograms were performed at 7 +/- 1 and 175 +/- 25 days after infarction. Left ventricular volumes, regional function and infarction artery status were quantified. Percutaneous transluminal coronary angioplasty (PTCA) was performed in the early angiogram in 31 patients. RESULTS: In the early angiogram, 13 patients showed ventricular remodeling (end-diastolic volume > 90 ml/m2). A larger extent of dysfunction was the only predictor (p < 0.002) of early remodeling. At 6 months, a smaller, early end-diastolic volume (p < 0.0001) and a poorer regional function recovery (p < 0.05) were independently related to late diastolic enlargement, and a poorer regional function recovery (p < 0.0001) and a smaller, early end-systolic volume (p < 0.009) were independently related to late systolic enlargement. One patient with compared with 20 patients without early remodeling (p < 0.04) presented with late remodeling (increment of the end-diastolic volume > 20% at 6 months). In patients with early remodeling, the end-diastolic volume did not change significantly (101 +/- 13 vs. 94 +/- 22 ml/m2, NS) at 6 months; despite this, they maintained larger diastolic volumes than patients with late remodeling (81 +/- 12 ml/m2, p < 0.04) at 6 months. Infarction artery status did not influence the evolution of ventricular volumes and regional function. CONCLUSIONS: (1) A large infarct size is the main determinant of postinfarction remodeling. (2) Such infarct size-dependent ventricular dilation occurs early and does not tend to increase in late stage; in contrast, some cases of intermediate-large size infarcts without early remodeling exhibit late remodeling associated with a poor late recovery of regional function. (3) Recovery of regional function (indicating myocardial viability) rather than infarction artery status plays a role in the late ventricular remodeling process.     

糖尿病和非糖尿病急性前壁心肌梗死晚期成功血运重建术后左室功能的变化及其与存活心肌的关系

目的:比较糖尿病和非糖尿病前壁急性心肌梗死(AMI)晚期成功血运重建术对心肌梗死后远期左室功能和预后的影响以及与存活心肌的关系.方法:选择依据病史、心电图和心肌损伤标志物等检查证实为首次发作的前壁AMI,并于发病后2周左右接受冠状动脉介入治疗术(PCI)的患者共计125例,其中参照WHO诊断标准确诊为并发糖尿病者(A组)43例,未并发糖尿病者(B组)82例.PCI前行超声心动图检查,了解左室功能和梗死相关区域存活心肌的情况.详细分析和记录PCI前后冠状动脉造影的结果.并分别于PCI前和术后6 h、24 h采取静脉血检测血清CK-MB和肌钙蛋白T水平.术后6个月重复超声心动图检查,了解左室功能和室壁活动异常的变化,并随访其间主要心血管事件的发生情况.结果:冠状动脉造影显示,与B组相比,A组PCI后即刻靶血管TIMI 2级血流所占的比例较多,TIMI 3级较少(分别为P<0.05和P<0.01).术后CK-MB和肌钙蛋白T增高者A组明显多于B组(25.6%∶9.8%,P<0.05).小剂量多巴酚丁胺超声负荷试验结果示A组中62.8%和B组中56.1%的患者有存活心肌,2组相比差异无统计学意义(P>0.05).急性期2组左室射血分数(LVEF)、左室舒张末期容积指数(LVEDVI)、收缩末期容积指数(LVESVI)以及室壁运动积分(WMS)基本相同(均P>0.05).术后6个月随访,B组WMS明显减少,LVEF明显增高;而A组LVEF和WMS均无明显改善,LVEDVI反而增加;2组相比LVEDVI、LVESVI、LVEF和WMS均有明显差异(分别P<0.05和P<0.01).随访期间2组主要心血管事件的发生率差异无统计学意义(18.6%∶11.0%,P>0.05).结论:糖尿病AMI晚期成功血运重建对远期左室功能的改善作用较非糖尿病者差,其结果可能与糖尿病患者晚期PCI后缺血心肌未能得到有效再灌注或再灌注加重心肌损伤有关,而术前存活心肌可能不是影响其疗效的主要原因.     

Relation of circulating interleukin-6 to left ventricular remodeling in patients with reperfused anterior myocardial infarction

BACKGROUND: During the remodeling process after myocardial infarction (MI), the expression of proinflammatory cytokines is enhanced in the myocardium. However, only a few clinical studies have been conducted on cytokine involvement in left ventricular (LV) remodeling after MI. HYPOTHESIS: Circulating proinflammatory cytokines may be involved in LV remodeling in patients with reperfused MI. METHODS: We studied 25 patients with acute anterior MI who had undergone coronary reperfusion therapy, and 10 normal control subjects with no cardiac disease. In all patients, LV ejection fraction, end-diastolic volume index (EDVI), and end-systolic volume index (ESVI) were determined using left ventriculography at the acute phase and 6 months after onset. The delta EDVI and delta ESVI were calculated as the value of LV volume reduction, suggesting LV reverse remodeling. Serum levels of interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha were measured using enzyme-linked immunosorbent assay. RESULTS: Serum levels of IL-6 and TNF-alpha at the acute phase were significantly higher in patients with MI than in control subjects (both p < 0.05). The IL-6 levels correlated well negatively with delta EDVI (r = 0.779, p = 0.039), whereas no correlation was found for TNF-alpha. According to multivariate analysis, IL-6 at the acute phase was a significant independent predictor for LV remodeling after reperfused MI (p = 0.007). CONCLUSIONS: Circulating IL-6 levels correlated closely with LV geometric changes during the remodeling process in patients with reperfused MI. Our study addresses the usefulness of another marker for LV remodeling after MI.     

Early prediction of 30-day mortality after Q-wave myocardial infarction by echocardiographic assessment of left ventricular function--a pilot investigation

BACKGROUND: The GUSTO angiographic substudy demonstrated that left ventricular function measured 90 min after thrombolytic therapy was given had important prognostic implications at 30 days in patients with an acute myocardial infarction (MI). HYPOTHESIS: Thirty-day prognosis after Q-wave MI can be determined by early echocardiographic assessment of left ventricular function. METHODS: Using transthoracic echocardiography, semiquantitative ejection fraction and wall motion score index was assessed prospectively in 201 consecutive patients within 24 h following Q-wave MI. Independent experts blinded to the patient's status performed the echocardiographic assessment. All patients received standard medical care as dictated by the attending cardiologist. RESULTS: Of the 201 patients, 24 (11.9%) died within 30 days, with 70% of the deaths occurring within 10 days after the infarction. Three deaths occurred in the 120 patients with an ejection fraction > or = 45% (2.5% mortality rate). In contrast, 21 deaths occurred among the 81 patients with an ejection fraction <45% (25.9% mortality rate) p = 0.0003. Two of the three patients who died in the high ejection fraction group died as a result of intracerebral hemorrhage from thrombolytic therapy. Ejection fraction was lower in nonsurvivors (32.3+/-10.3 vs. 46.3+/-13%) than in survivors, p < 0.0002. Wall motion score index (WMSI) of < 1.4 was associated with a 2.9% 30-day mortality (two deaths in 76 patients); WMSI of > or = 1.4 was associated with a 17.6% 30-day mortality (22 deaths in 125 patients), p = 0.0007. Average WMSI was higher in the nonsurvivors (1.95+/-0.5) than in survivors (1.52+/-0.45), p = 0.00001. CONCLUSIONS: Echocardiographic assessment of left ventricular function during the first 24 h after an acute Q-wave MI can be performed in all patients regardless of stability. High-risk patients are identified early in the hospital course, with relative ease, at no risk and at an acceptable cost. An ejection fraction < 45% or WMSI > or = 1.4 identifies patients who are at a high risk of dying within 30 days. These are the patients who may benefit most from aggressive medical therapy and early angiography to assess coronary pathology.     

螺内酯抑制急性前壁心肌梗死患者的左室重构

目的探讨急性前壁心肌梗死患者口服螺内酯对于左室重构的影响。方法将急性前壁心肌梗死患者随机分为两组。对照组30例,接受血管紧张素转换酶抑制剂、β-受体阻滞剂、抗血小板、调脂药物等常规处理。螺内酯组30例,在常规治疗基础上加用螺内酯（40mg,每日1次）。随访1年,并检测脑钠尿肽（BNP）及超声心动图以评价左室功能和左室容积。结果6和12月时螺内酯组血清BNP水平明显低于对照组[（355±74）ng/Lvs（418±77）ng/L,P<0.05和（316±72）ng/Lvs（389±67）ng/L,P<0.05],且12月时螺内酯组较对照组左室舒张末期内径（LVEDD）、左室收缩末期内径（LVESD）明显缩小[LVEDD:（49±6）mmvs（53±5）mm,P<0.05;LVESD:（37±5）mmvs（40±4）mm,P<0.05]。结论螺内酯可抑制急性前壁心肌梗死患者左室重构。     

Effect of hepatocyte growth factor on left ventricular remodeling after acute myocardial infarction in canine

Background and objectives To investigate the effect of hepatocyte growth factor (HGF) on left ventricular (LV) remodeling after acute myocardial infarction (AMI). Methods AMI was produced by ligation of proximal left anterior descending coronary artery(LAD) in 12 mongrel canines. These animals were randomized into 2 groups. In HGF group (n=6), canines were injected with pcDNA3-HGF lml (about 300ug) at the margin of infarcted myocardium; in control group (n=6) canines were injected with equal volume of normal saline. Cardiac function and left ventricular remodeling were evaluated with echocardiography at 1, 4, 8 weeks after MI. LV myocardium specimens were obtained at 8 weeks and stained with hematoxylin and eosin for histological examination or with sirius red to assess the collagen content. Results Compared with control group, LVEF in HGF group was significantly higher at 4 weeks (49.61+6.66 vs 39.84+6.39; P＜0.05) and at 8 weeks (51.57+8.53 vs 40.61+7.67; P＜0.05) after AMI, while LVESV was significantly lower in HGF group than that in control group at 8 weeks after AMI (18.98+3.47 vs 25.66+5.86; P＜0.05). Posterior left ventricular wall thickness decreased significantly from 1 wk to 8 wks after AMI in control group, while remained unchanged in HGF group. Compared with control group, histological examination showed more neovascularization and less scar, and sirius red staining indicated higher volume of type Ⅲ collagen (7.10&#177;4.06% vs 3.77&#177;1.09%; P＜0.05) and lower collagen Ⅰ/Ⅲ ratio value (1.11&#177;0.52 vs 2.94&#177;2.48; P＜0.05)in HGF group. Conclusion HGF gene transfer might improve cardiac function and LV remodeling after acute myocardial infarction by stimulating angiogenesis, reducing fibrosis, and reducing myocardial scarring.     

多普勒超声心动图评价急性心肌梗塞后左室重构及心功能改变

应用多普勒超声心动图对56例不同部位急性心肌梗塞（AMI）后患者及40例正常人左室结构（LVR）、收缩舒张功能参数进行对比分析研究。结果显示AMI后患者左室舒张及收缩末期内径、左心室舒张末期容积、左心室收缩末期容积、左室射血前期与射血时间比、舒张晚期峰值血流速度、A峰面积增大；射血分数、短轴缩短率、舒张早期峰值血流速度、E峰／A峰面积则降低，两组间比较有极显著性差异（P＜0．01）。认为AMI后患者心脏不同程度的发生了LVR及收缩舒张功能减退。     

Full recovery of contraction late after acute myocardial infarction: determinants and early predictors

OBJECTIVES—To assess the relative value of electrocardiographic, echocardiographic, angiographic, and in-hospital therapeutic indices for predicting late functional recovery after acute myocardial infarction, and to determine the variables associated with absence of recovery, partial recovery, and full recovery.
DESIGN—Prospective observational follow up study.
SETTING—Teaching hospital.
PATIENTS—74 consecutive patients with a first uncomplicated acute myocardial infarct.
INTERVENTIONS—Dobutamine-atropine stress echocardiography was performed mean (SD) 5 (2) days after the acute event. Quantitative angiography was available in all patients before hospital discharge. A follow up resting echocardiogram was obtained 12 (2) months later.
RESULTS—Functional recovery (partial, n = 18; full, n = 27) was observed in 45 of the 74 patients. Recovery was associated with earlier thrombolytic treatment (p = 0.008), earlier peak concentration of creatine kinase (p = 0.009), greater contractile reserve (p = 0.0001), non-Q wave acute myocardial infarction (p = 0.002), and more frequent elective angioplasty of the infarct related vessel (p = 0.0004). Three independent variables were selected stepwise from multivariate analysis for predicting late recovery: contractile reserve (χ² = 24.2, p < 0.0001); non-Q wave infarction (χ² = 15.7, p = 0.0001); and the time from symptom onset to thrombolysis (χ² = 4.94, p = 0.026). Three independent variables predicted full recovery: contractile reserve (χ² = 17.2, p = 0.0001); non-Q wave infarction (χ² = 10.1, p = 0.0016); and elective angioplasty of the infarct related artery (χ² = 4.53, p = 0.033). Only contractile reserve (χ² = 17.0, p < 0.001) was selected from the multivariate analysis for its ability to distinguish between partial recovery and absence of recovery.
CONCLUSIONS—Late recovery of contraction relates to earlier treatment, which is associated with lower infarct size unmasked by a non-Q wave event and the presence of contractile reserve. Elective coronary angioplasty of the infarct related artery before hospital discharge is associated with full recovery.


Keywords: myocardial infarction; echocardiography; prognosis; angioplasty     

Left ventricular thrombosis and arterial embolism after thrombolysis in acute anterior myocardial infarction: predictors and effects of adjunctive antithrombotic therapy

The prevalence of left ventricular (LV) thrombosis and incidenceof arterial embolism after acute anterior myocardial infarction(AAMI) treated with streptokinase 1.5 x 10⁶ IU intravenouslywas studied in 136 patients enrolled consecutively in five cardiologicalcentres. Adjunctive antithrombotic therapy was administeredaccording to the routine of each centre. Thrombus formationwas studied by two-dimensional echocardiography, and eventsof arterial embolism recorded. LV thrombosis was found in 37 (27.2%) of the patients. In asubgroup of 53 patients receiving post-thrombolytic therapywith acetylsalicylic acid only, a thrombus developed in 14 (26.4%).The thrombus prevalence among patients given high-dose heparinwas significantly lower than among those receiving either low-doseheparin or no heparin (4/30 vs 33/106, P = 0.045). Logistic regression analysis suggested that severe LV wall motionabnormality (P & 0.001) and avoidance of treatment withhigh-dose heparin(P = 0.023) were independent predictors ofLV thrombus formation. Only one patient (0.7%) suffered arterial embolism (ischaemicstroke). In conclusion, LV thrombosis is frequent after thrombolytictherapy for AAMI, and impaired LV wall motion represents anindependent predisposing factor. Low-dose heparin and acetylsalicylicacid seem less effective for LV thrombus prophylaxis than high-doseheparin. The incidence of arterial embolism is low.     

Emergent angioplasty prevents left ventricular dilation in patients with acute anterior wall myocardial infarction and cardiogenic shock

BACKGROUND: Percutaneous transluminal coronary angioplasty (PTCA) reduces in-hospital mortality and improves long-term outcome in patients with acute myocardial infarction (MI) complicated by cardiogenic shock. However, no study has evaluated the effects of different reperfusion therapies on left ventricular (LV) dimension and cardiac function in long-term survivors of MI with cardiogenic shock. HYPOTHESIS: We investigated the effects of PTCA on the development of LV dilation in patients who survived MI complicated by cardiogenic shock. METHODS: We studied 34 patients with a first MI and cardiogenic shock in whom two-dimensional echocardiography was performed immediately after admission and 1 month after infarction. Group A consisted of 17 patients who underwent emergent PTCA during the acute phase of MI, and Group B consisted of 17 patients who did not undergo PTCA. We also studied 119 patients with a first uncomplicated acute anterior MI, including 53 who underwent PTCA (Group C) and 66 who did not (Group D). The length and wall thickness of the infarcted and noninfarcted endocardial segments were determined immediately after MI and 1 month later, and LV ejection fraction (LVEF) was measured during the chronic phase. RESULTS: The lengths of the infarcted and noninfarcted endocardial segments were significantly greater in Group B than in the other three groups (p < 0.05). The LVEF was significantly lower in Group B than in the other three groups (p < 0.05). CONCLUSIONS: We conclude that PTCA performed in patients during the acute phase of MI complicated by cardiogenic shock lowers in-hospital mortality and prevents both LV dilation and a decrease in LVEF.     

Effects of late coronary artery reperfusion on left ventricular remodeling persist for 10 weeks after experimental rat myocardial infarction and are associated with improved survival

Objective: To test the hypothesis that coronary artery reperfusion performed too late to reduce infarct size improves survival by altering left ventricular remodeling and preventing progressive left ventricular dilation.Background: Several clinical trials have suggested that late coronary artery reperfusion without infarct size reduction is associated with a survival benefit. Although the mechanism is not known, survival benefits could be related to decreased infarct expansion associated with late coronary artery reperfusion. Decreased infarct expansion results in decreased left ventricular volume, and the resulting decreased wall stress could prevent or attenuate progressive left ventricular dilation and improve survival.Methods: Rats (n=84) were randomized to undergo sham operation, permanent left coronary artery ligation, or 2 hours of left coronary artery ligation followed by reperfusion. Ten weeks later, hemodynamic measurements were made before and after volume loading. The rats were killed, the hearts were removed, and passive pressurevolume curves were obtained. The hearts were fixed at a constant pressure and analyzed morphometrically.Results: When examined 10 weeks after experimental myocardial infarction, late reperfusion's effects on left ventricular remodeling resulted in reduced left ventricular volume when compared to hearts with infarcts supplied by a permanently occluded coronary artery (1.9 ± 0.1 ml/kg vs. 2.1 ± 0.2 ml/ kg; p < 0.01). Although there was a trend toward less thinning (0.95 ± 0.13 mm vs. 1.00 ± 0.10 mm; p=NS) and less expansion (2.3 ± 0.4 vs. 2.8 ± 0.9; p=NS) in reperfused hearts compared to hearts with a permanently occluded coronary artery, changes in infarct shape 10 weeks after infarction were not significantly different. Reperfusion's beneficial effects on remodeling of noninfarcted myocardium were associated with improved survival. Mortality was higher in the permanently occluded rats than in the reperfused rats (35% vs. 12%; p < 0.05).Conclusion: Late coronary artery reperfusion has a beneficial effect on remodeling of noninfarcted myocardium that results in reduced left ventricular volume in rat hearts examined 10 weeks after infarction. These beneficial effects on left ventricular remodeling are associated with improved survival.     

EflFect of hepatocyte growth factor on left ventricular remodeling after acute myocardial infarction in canine

Background and objectives To investigate the effect of hepatocyte growth factor (HGF) on left ventricular (LV) remodeling after acute myocardial infarction (AMI). Methods AMI was produced by ligation of proximal left anterior descending coronary artery (LAD) in 12 mongrel canines. These animals were randomized into 2 groups. In HGF group (n=6), canines were injected with pc-DNA3-HGF 1 ml (about 300ug) at the margin of infarcted myocardium; in control group (n=6) canines were injected with equal volume of normal saline. Cardiac function and left ventricular remodeling were evaluated with echocardiography at 1,4, 8 weeks after MI. LV myocardium specimens were obtained at 8 weeks and stained with hematoxylin and eosin for histological examination or with sirius red to assess the collagen content. Results Compared with control group, LVEF in HGF group was significantly higher at 4 weeks (49.61 6.66 vs 39.84 6.39; P<0.05) and at 8 weeks (51.57 8.53 vs 40.61 7.67; P<0.05) after AMI, while LVESV was significantly lower in HGF group than that in control group at 8 weeks after AMI (18.98 3.47 vs 25.66 5.86; P<0.05). Posterior left ventricular wall thickness decreased significantly from 1 wk to 8 wks after AMI in control group, while remained unchanged in HGF group.Compared with control group, histological examination showed more neovascularization and less scar, and sirius red staining indicated higher volume of typeⅢcollagen (7.10±4.06% vs 3.77±1.09%; P<0.05) and lower collagenⅠ/Ⅲratio value (1.11±0.52 vs 2.94±2.48; P<0.05) in HGF group. Conclusion HGF gene transfer might improve cardiac function and LV remodeling after acute myocardial infarction by stimulating angiogenesis, reducing fibrosis, and reducing myocardial scarring.     

急性心肌梗死后左室重构临床研究

目的　探讨溶栓治疗对急性心肌梗死后左室结构和功能的影响。方法　对 36例首发急性心肌梗死患者于梗死后 4周和 12周进行超声心动图观察。分别测定左室舒张末期容积指数 (LVEDVI)、左室收缩末期容积指数 (LVESVI)、射血分数 (EF) ,作为反映左室结构和功能变化的指标。结果　急性心肌梗死后LVEDVI、LVESVI均明显增高 (分别为P <0 0 1,P <0 0 5 )。 4周和 12周检查发现 ,溶栓组LVEDVI、LVESVI无明显差异 (分别P>0 0 5 ,P >0 0 5 ) ,EF值明显增大 (P <0 0 5 ) ;未溶栓组LVEDVI、LVESVI明显增大 (分别为P <0 0 5 ,P <0 0 5 ) ,EF值无明显变化 (P >0 0 5 ) ;对 4周和 12周的检查结果作组间比较发现 ,溶栓组LVEDVI、LVESVI均小于未溶栓组 (P <0 0 5 ) ,EF值溶栓组高于未溶栓组 (P <0 0 5 )。结论　溶栓治疗能有效地抑制急性心肌梗死后左室重构 ,改善心功能。     

肝细胞生长因子对急性心肌梗死后左室重构的预测作用

目的: 探讨血清肝细胞生成因子(HGF)对急性心肌梗死(AMI)后早期左室重构的预测价值。方法: 36例AMI患者入院时及发病7 d测定血清HGF水平;AMI其中的26例分别于发病后7~10 d及发病后3个月行超声心动图检查,3个月时左室舒张末期容积指数（LVEDVI）与7~10 d时比增加≥5 ml/m2定义为左室重构组(n=11),对两组血清HGF值进行比较。结果: AMI患者入院时血清HGF浓度较对照组明显升高［(809±288)ng/L vs.(620±162)ng/L,P<0.01］,7 d时升高更显著［(1 607±1 355)ng/L,P<0.01］。发病7 d时血清HGF浓度在左室重构组较非左室重构组升高［(2 216±1 522)ng/L vs.(1 176±593)ng/L,P<0.05］,而入院时两组浓度则无显著差异。结论: AMI时血清HGF浓度升高,AMI后7 d时增高的血清HGF可能预示心室重构。     

急性心肌梗死后左心室重构及其防治

本文简述了急性心肌梗死后左心室重构的发生机制、时间、后果、影响因素及防治措施等     

急性心肌梗死与左室重构

急性心肌梗死(AMI)后左室发生细胞学,分子学及细胞间质的变化,进而引起左室在大小、形态、组织结构和功能状态的改变,此即目前许多研究所提及的AMI后的左室重构.AMI后左室的重构贯穿于整个病程的始终,成为影响AMI患者近远期预后的主要原因之一.     

急性心肌梗死后存活心肌对梗死相关血管晚期血运重建术后左室功能的影响

目的探讨存活心肌对急性心肌梗死(AMI)后梗死相关血管(IRA)晚期血运重建术后远期左室功能以及左室重构的影响.方法69例AMI未接受早期再灌注治疗者,于发病10～21 d行IRA经皮冠状动脉血运重建(PCI)术,术前于AMI发病后5～10 d应用小剂量多巴酚丁胺(5和10μg·min-1·kg-1)超声心动图负荷试验检测存活心肌,并分别测定和计算给药前后左室腔大小、左室射血分数(LVEF)以及室壁运动积分(WMS).按有无存活心肌分为存活心肌组和无存活心肌组,超声心动图随访术后6个月时两组左室腔大小、LVEF和WMS的变化.结果157个运动异常节段中89个节段(57%)有存活心肌,有存活心肌组26例(占38%),无存活心肌组43例(占62%).存活心肌组术后6个月LVEF较术前明显提高(P＜0.05),收缩末期容积指数(LVESVI)和WMS明显降低(P＜0.05和P＜0.01);而无存活心肌组LVEF较术前明显降低(P＜0.01),LVESVI和左室舒张末期容积指数(LVEDVI)较术前明显增加(P＜0.05),WMS无明显变化.存活心肌组多巴酚丁胺负荷时的LVEF和WMS明显改善,且与6个月时的测定值相近;而无存活心肌组PCI前应用多巴酚丁胺LVEF和WMS均无明显变化.结论AMI后有存活心肌者晚期血运重建有利于改善远期左室功能和减少左室重构.心肌梗死后早期小剂量多巴酚丁胺负荷状态下左室收缩功能的提高预示晚期血运重建术后心功能改善.